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WaterHeater drain pan required in basement

Buelligan

Registered User
Joined
Oct 7, 2010
Messages
124
Location
Eastern Panhandle WV
Afternoon guys,

I searched and found some discussion about this but no definitive answer in a 2010 thread. So I am starting a new thread based on 2015 IRC.

2801.6 Required pan. Where a storage type tank... will cause damage, the tank shall be installed in a pan ....

Paraphrased the key parts, and the question is about the use of the word damage. I read in the other thread that "structural" was removed at some point. I also read in the commentary, assuming it implies a degree of "intent", that where "structural damage" will occur. So our "understanding" of intent was that if a leak went undetected for a period of time and it could damage the "structure", the pan is required. We have a lot of basements here and not all of them include a floor drain. So does "damage" include the finished area in a basement? We do not want to make people cut up concrete floors to put in drains for the rare occurrence of a water heater leak, when no "structural" damage is likely to occur in a basement. Some wet carpet and drywall is not going to bring the house down. So how do you guys enforce the pan under a water heater in a "finished" basement? Thanks
 
I believe the intent is wood framing damage, and the pan is to help with that water removal due to code restrictions on the PRV. The PRV drain should not have directional fittings like elbows and should drain into the pan. Am I wrong?

Could a leaking WH cause damage in a basement, you betcha, but I would not require it if there's a floor drain near by.
 
The only place we require it is in the attic or some other concealed space where a leaking water heater would not be observed for a period of time.
 
2015 UPC
Requires a pan be installed when WH is installed in "an attic or in/on a attic-ceiling assembly, floor ceiling assembly, or floor-subfloor assembly where damage results from a leaking water heater"
So a basement is not specifically mentioned a pan would not be required. Under the UPC the pressure relief can not discharge into the drain pan so a floor drain would be required in a basement
 
Around here, in new construction, I don't show a safe pan on a water heater located in basement that has exposed slab floor and a floor drain somewhere in the vicinity. In an existing structure with existing water heater, i don't think i would ask for a floor drain to be added.
 
Well wherever the water heater is installed.....if a leak can cause damage and a pan can be drained, the pan is required. The damage is not defined or quantified. Every water heater, anywhere and any damage.

In a basement there is most likely no gravity drain available. In the middle of a slab on grade house on the ground floor there is most likely no gravity drain available. A couple times each year I see the result of a leaking water heater that lacked a gravity drain. Water heaters should be in garages or outside. You folks living in harsh climates would disagree.....
 
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The 2015 added very helpful language for what you are dealing with. Read the next section down, p2801.6.1. "Where a pan drain was not previously installed, a pan drain shall not be required for a replacement water heater installation." You can still have the pan installed, but cap the drain and then use a water monitoring device.
BTW: I have a very comprehensive online, on-demand course that covers everything about water heaters and furnaces, based on the 2015. You can take the course for free, if you haven't already taken a free course from me. Use the coupon code "welcome" www.buildingcodecollege.com
 
Well wherever the water heater is installed.....if a leak can cause damage and a pan can be drained, the pan is required. The damage is not defined or quantified. Every water heater, anywhere and any damage.

In a basement there is most likely no gravity drain available. In the middle of a slab on grade house on the ground floor there is most likely no gravity drain available. A couple times each year I see the result of a leaking water heater that lacked a gravity drain. Water heaters should be in garages or outside. You folks living in harsh climates would disagree.....

Around here......everything gravity drains ..........slab in grade, crawl, full basement......gravity drains.
 
2015 UPC Under the UPC the pressure relief can not discharge into the drain pan so a floor drain would be required in a basement

That's odd, does the UPC allow elbow or other directional fittings on a PR to get to that drain?
 
99% of the new houses I see have basements, and 99% of those have the WH in a room in the basement right beside the furnace. Uncovered concrete floor and a floor drain right there. No pan required.

99% of the remodels / rental houses I see have the WH stuck wherever it was easiest for the hack plumber to hook them up. Those are mostly on enclosed porches or in closets on wood floors, and those all get a pan.
 
That's odd, does the UPC allow elbow or other directional fittings on a PR to get to that drain?
Yes. You can go horizontal and down with your piping. You can not go vertical (up) with it therefore a basement does require a floor drain and the state has determined they can not go in a crawl space because you can not meet the T&P drain discharge requirements. In new construction they are installing them on the main floor on a pan and the drain pan and T&P drains are then piped to discharge through the rim into the garage due to our harsh climate
Replacement water heaters wherever they are located you will install a pan with a plug and water monitoring device as Glenn described above
 
I agree with ICE I post #6, and do not believe a consensus to define potential damage will provide you with a catchall answer. A case-by-case basis of where the water tank is located could help guide your determination.

The intent for damage, including carpet and tiles, could be if a leak will go unnoticed and may require replacement owing to rot, mildew or mold.

For example where the basement is unfinished when the water heater is installed, will you make them install a pan based on an assumption of “what if” the basement becomes finished?

The answer and remedy for above example would be as Glenn provided in post #7, though the does not require a “drip” pan, but they may decide to install one to help avoid future damage. In this case, “a consensus was that a pan with no drain is better than no pan at all. If the water heater tank begins to leak and there is a pan present, the occupant may notice water in the pan and realize that it is not a normal condition. This is opposed to a situation where there is not a pan and the leaking water flows to an unobservable location and does for a long time, creating damage” and an unhealthy environment.

Thus, the requirement in the basement could be dependent on the potential traffic at the location of the water tank. Noted this consensus did not address absence during vacancies when the home may be unoccupied during extended periods. You know those times the spouse says along the way “did I turn the water off, unplug the iron, lock the front door, leave the light on, etc.?”

And if there’s any consistency along this line thought, overflow for bathtubs had been required to prevent flooding, the 2018 IRC no longer require an overflow for bathtubs, not because of the likelihood of attendance may prevent damage from overflow, but of the difficulty of maintaining cleanliness inside the overflow.

Your opinions may vary with cold number of kids, pet alligators, bills . . .
 
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